1. Field of the Invention
The present invention is broadly concerned with an improved closed loop comminuting and dehydrating system which provides numerous advantages, including expanded application to viscid materials, increased efficiency, enlarged capacity, and emissions control. More particularly, it is concerned with a comminuting and dehydrating system having a cyclonic comminuter unit, a blower, a collection chamber, and a valve-controlled conduit intercoupling the blower and closed collection chamber for equalizing pressure in the chamber. An injection port permits introduction of materials directly into the low pressure zone of the cyclone, to prevent caking when liquid or viscid materials are processed. Air escaping from the top of the cyclonic unit is captured and conveyed to a dust collection unit. Alternatively, the air may be conveyed to a secondary cyclonic unit equipped with a filtration system and a closed collection chamber.
2. Description of the Related Art
Devices for comminuting and dehydrating are well known. One example is referenced in U.S. Pat. No. 5,236,132 issued to the applicant on Aug. 17, 1993, which patent is incorporated herein by reference. Such prior art comminuting and dehydrating devices comprise a cyclone chamber mounted atop a conical body, an adjustable coaxial sleeve for introducing material to be processed, a damper for reducing air flow through the sleeve, and a blower. A feeder unit is interposed between the blower and the chamber, and material may also be introduced into the chamber through the coaxial sleeve. Processed material may be deposited on a conveyor, pneumatic conveyance system, or collected in an open bin. Such cyclonic comminution devices are suitable for processing materials such as minerals, plants, food products, recyclable materials, and soil.
They may be employed for pulverizing and separating ores such as gold, silver, copper, kaolin and which are recovered from rock formations presenting a different density or structure than the ore. They may also be employed to pulverize and dehydrate materials such as gypsum, fly ash, foundry shag, coal, coke, phosphates and residual products of refining and distillation processes, as well as animal shells and crustaceans as well as bones, diatomaceous earth and soil structures. They may be employed to pulverize, dehydrate, and preserve food products such as grain, and grain components such as gluten and for fractionalization of the starch protein matrix, as well as for enhancement of lipid or fiber content for further processing or defatting. They may be employed for fragmentation and dehydration of fibrous foods such as carrots, apples, beans, and spinach and for pulverization and dehydration of lignocellulosic biomass materials such as trees, seaweed, straw, peat moss, waste paper and animal wastes. Such cyclonic comminuter dehydrator units may also be employed in recycling for pulverizing glass, metals, plastic and organic materials so that such components may be mechanically sorted and separated. The units may also be used to pulverize and dehydrate soil and to separate it from rock, ash, boron, hydrocarbons and other contaminants, either alone or in conjunction with washing, thermal, biological, or other treatment processes.
However, such comminuter dehydrators are not particularly suitable for processing viscid materials or materials including additives such as milk whey, raw eggs or wheat gluten. Moreover, such devices emit small particles of the processed materials into the air as dust. Such emissions not only reduce the efficiency of the process, but may be environmentally undesirable.